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Motherboard Compatibility between LC 580 and Later Systems
Posted by: Zhinü on 2022-12-14 16:11:16
Are the motherboards from later AIO systems (5200, 5500, etc) compatible with the LC 580?

I know that the LC 520/550/575 don’t support it without heavy case modding and cable rewire (that’s why they work with CCs), but the LC 580 has a harness cable that looks similar to the later macs.

I would test it myself (I own a LC 580) but I gave away the 5260 board I was saving.
Posted by: Phipli on 2022-12-14 16:12:57
You have to mod the wiring harness a little - they added 3.3V to the PCI boards. It can be done though and there are pinouts / instructions online.
Posted by: Zhinü on 2022-12-14 16:15:46
You have to mod the wiring harness a little - they added 3.3V to the PCI boards. It can be done though and there are pinouts / instructions online.
I’ve seen it done to “Takky” CCs, but I don’t think i’ve seen it to upgrade LC580s.

I also noticed that on the Takky website it does mention that the 5200/5300 motherboards do not need 3.3V. Do they actually?
Posted by: Phipli on 2022-12-14 16:23:08
I’ve seen it done to “Takky” CCs, but I don’t think i’ve seen it to upgrade LC580s.

I also noticed that on the Takky website it does mention that the 5200/5300 motherboards do not need 3.3V. Do they actually?
I believe you don't need 3.3v if you're not using PCI, but I'm not certain what is connected where the 3.3v would be. You'd want to check to make sure it wouldn't cause a short. Its years since I was reading about it so probably best for someone else to give details if you can't see the answer in an old thread. I think someone asked something similar a couple of weeks ago.
Posted by: Phipli on 2022-12-14 16:30:43
This is a similar discussion:

Posted by: Zhinü on 2022-12-14 17:12:22
I noticed that one of them mentioned “see sig” so I assume there’s a chart or something that determines that?

As for 3.3V, I see that the only location the 3.3V goes to is P8 on the power header on the motherboard. I unfortunately don’t have the pinout for the LC580 boards though. (It’s on the Takky website, can’t seem to send the image though.)

Posted by: Zhinü on 2024-09-04 14:33:07
So I got a 6300CD board from a friend and tossed it into the LC580, and it seems to work perfectly fine, minus the bracket not fitting. Wonder how far I could go with this…
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